1. Field of the Invention
The present invention relates to a method of allowing a user to enter characters into electronic equipment such as a mobile telephone or a computer by selecting a character on a software keyboard displayed on a display screen of the electronic equipment using a cursor key, and displaying the selected character on the display screen.
2. Description of the Prior Art
Some mobile telephones have a function of storing in a memory telephone numbers each associated with its destination name such as a person's name or a company's name, and a function of searching for a telephone number from its corresponding destination name when a user makes a call. When a user uses such functions, the user needs to enter a destination name as well as a corresponding telephone number. In such a case, since a number of keys cannot be arranged on the control panel of such a mobile telephone, the user has to enter the destination name to the mobile telephone through the use of a ten-button keypad found on the control panel intended for typing in a telephone number.
Referring now to FIG. 9, there is illustrated a plane view showing the control panel of a prior art mobile telephone through which a user can type in letters, and on which user-entered letters can be displayed, as disclosed in for example Japanese Patent Application Laying Open (KOKAI) NO. 6-348383. In the figure, reference numeral 101 denotes the main body of a mobile telephone, 102 denotes the display screen of a display such as a liquid crystal display, and 103 denotes a keypad. The keypad 103 includes a numeric keypad 104 containing ten number keys to each of which two or more letters of the alphabet and letters of the Japanese alphabet are assigned. A table indicating a correspondence between each of the ten number keys and two or more letters of the alphabet and letters of the Japanese alphabet assigned to each of the ten number keys is stored in a ROM in which a control program for controlling a built-in CPU is also stored.
Referring next to FIG. 10, there is illustrated a block diagram showing the internal structure of the prior art mobile telephone shown in FIG. 9. In the figure, reference numeral 110 denotes an RF circuit connected to an antenna 111, 112 denotes a central processing unit or CPU connected to the RF circuit 110 by way of an input/output or I/O circuit 113, 114 denotes a ROM in which a control program for controlling the CPU 112 is stored, 115 denotes a RAM in which data needed for the control program to control the CPU 112 are stored, 116 denotes a liquid crystal display control circuit for displaying data from the CPU 112 on the screen of a liquid crystal display 117, and 118 denotes a font ROM for storing font data to be furnished to the liquid crystal display control circuit 116. The keypad 103 is connected to the CPU 112 by way of another input/output or I/O circuit 119. The mobile telephone further comprises an audio circuit, not shown, including a microphone, a speaker, and so on.
As shown in FIG. 9, three letters "A", "B", and "C" of the alphabet are assigned to the number key "2", on the numeric keypad 104. When the number key "2" is pressed once in character input mode, the letter "A" is displayed on the screen 102 of the liquid crystal display. When the number key "2" is pressed twice in character input mode, the letter "B" is displayed on the screen 102 of the liquid crystal display. When the number key "2" is pressed three times in character input mode, the letter "C" is displayed on the screen 102 of the liquid crystal display. In this manner, each time the user presses the number key "2", the letter displayed on the screen 102 is changed in the order of "A", "B", and "C". In order to select a desired one from the letters and then confirm the selection, the user should wait a predetermined time or press another key while a desired one of the letters is displayed. For example, in order to enter and display the letter "C" on the screen, the user has to press the number key "2" three times and then press another key to confirm the selection, that is, the user needs four sequential key touches.
Accordingly, a problem with the prior art method of allowing a user to enter characters into electronic equipment is that a large number of key operations is needed when the user enters characters. In addition, a second problem is that users are subject to great stress when entering characters into electronic equipment because they have to enter characters while looking at characters marked on each of the number keys and user-entered characters displayed on the screen 102 alternately.
Referring next to FIG. 11, there is illustrated a plane view showing the control panel of another prior art mobile telephone through which a user can type in letters of the alphabet, and on which user-entered letters can be displayed, as disclosed in for example Japanese Patent Application Laying Open (KOKAI) NO. 7-322358. In a display unit 107 of the main body 106 of the mobile telephone, there are provided a letter display region 107a in which selectable letters are displayed, and an input region 107b in which user-entered (or user-selected) letters are displayed. If a user presses a number key on a numeric keypad 108, letters associated with the pressed number key are displayed in the letter display region 107a. After that, the user can select a desired letter from among the characters on-screen and display the desired letter in the input region 107b by moving a cursor 107c to the position of the desired letter and then pressing a SEL key on an operational keypad 109 so as to confirm the selection of the desired letter under the cursor 107c.
While the user can enter letters into the prior art mobile telephone as the user looks at the display screen, problems with the prior art mobile telephone are that the user has to take extra special care on entering characters because the user has to search for a number key to which a desired character to be entered is assigned in order to manipulate the number key, and the user has difficulty in manipulating keys when entering letters.